On February 9th, 2016, we announced the release of Cloudera Enterprise 5.5.2. Shortly after that, we discovered a severe bug in Cloudera Manager 5.5.2, so we decided to remove the release. CDH 5.5.2 is not affected by this bug.
We will release Cloudera Manager 5.5.3 and CDH 5.5.2 soon. Cloudera Manager 5.5.3 will include all the improvements, fixes, and changes that were in Cloudera Manager 5.5.2, plus the fix for the severe bug that was discovered.